Mechanism for intermittent and progressive drill feeding



Sept. 8, 1936. E J, NGSBU' Y' 2,053,399

MECHANISM FOR INTERMITTENT AND PROGRESSIVE DRILL FEEDING Fild July 14,1953 10 Sheets-Sheet 1 men/fir: Z'dzoard JWJEM? I you 10 Sheets-Sheet 2E'. J. KINGSBURY Filed July 14, 1.955

.-- LL L- L-L- MECHANISM FOR INTERMITTENT AND PROGRESSIVE DRILL FEEDINGSept. 8, 1936.

Sept. 8, 1936.

J E. J. KINGSBURY MECHANISM FOR INTERMITTENT AND PROGRESSIVE DRILLFEEDING Filed July 14, 1953 10 Sheets-Sheet 5 Inventor: l'mwaz'dhi yawg,

Sept. 1936- I E.'. J. KINGSBURY 7 2,053,399

MECHANISM FOR INTERMI TTE NT AND PROGRESSIVE DRILL FEEDING Filed July14, 1933 10 Shets Sheet 4 P 1936- E. J. KINGSBURY 2,053,399

MECHANISM FOR INTERMITTENT AND PROGRESSIVE ,DRILL FEEDING Filed July 14,1933 I 10 Sheets-Sheet 5 J9 PHI:

7 Int/8%).- 5212mm @Z'Kz'gaaay,

Sept. 8, 1936. E. J. KINGSBURY 2,053,399

MECHANISM FOR INTERMITTENT AND PROGRESSIVE DRILL FEEDING 6 t e e h s s te e h S 0 l Sept. 8', 1936. E. J/KINGSBURY I 2,053,399

MECHANISM-FOR INTERMITTENT AND PROGRESSIVE DRILL FEEDING Filed July 14,1933 10 Sheets-Sheet '7 Eda/arm JIKZ'WJZW Sept. 8, 1936. J. KINGSBURY2,053,399 7 MECHANISM FOR INTERMITTENT AYND PROGRESSIVE DRILL FEEDINGFiled July 1933 10 Sheets-She et 8 Sept. s, 1936.

E. J. KINGSBURY MECHANISM FOR INTERMITTENT AND PROGRESSIVE DRILL FEEDINGFiled July 14, 1933 10 Sheets-Sheet 9 Sept. 8, 1936. E. J. KINGSBURY2,053,399

MECHANISM FOR INTERMITTENT AND PROGRESSIVE DRILL FEEDING Filed July 14,1933 v 10 Sheets-Sheet 10 memrt Z'ward el'jfi'yszur 3/ Patented Sept. 8,1936 LIECHANISM FOR INTEBMITTENT AND PROGRESSIVE. DRILL FEEDINGnuweraseslm Kingsbury, Keene, N. n. Application July 14, 1933, Seriala... 680,489

19-.Ola.ims. (01. 11-32) This invention relates to an apparatus whichoperates by an intermittent and progressive feeding movement.

While capable of other uses, it is particularly adapted for employmentin machine tools, and more especially to drill devices of horizontal andvertical type where a drilling tool is fed forward.

intermittently and progressively.

One of the features of the present invention relates to a control meansby which the system may be shifted through a shifting of the control Imeans, whereby an adjustment is effected, as for example, following thegrinding of a drill, without any change in the distance of movements 1accomplished during a cycle, so that this simple movement of the controlmeans will effect the necessary readjustment following grinding of thedrill, etc.

Another feature of the present invention is the provision of means forproducing an intermittent return and re-feeding of a carriage withrespect to its frame, wherein each feeding movement involves a travel ofthe carriage to a greater distance with respect to. the framerepresenting an increment of feeding movement, these increments beingsuccessively less in amount.

Another feature of the present invention is the provision of a controlsystem for such a device which is simple of adjustment and compact inarrangement, and which by'external indicators may reveal the'positionof. the operating parts during the course of the cycle of movements.

Another feature of the present invention is the provision of controlmeans for the movement of the carriage .with respect to the frame,whereby the carriage starts at a withdrawn position and performssuccessive and intermittent progressive feeding movements, returning ineach intermittentmovement to a distance less than that of bringing thecarriage-to its initial position, with an immediate return for a'furtherintermittent operation, followed by a final withdrawal to the initialposition. Inthisway, the .tool (as for example, adrill) is fullywithdrawn'from the work in the initial position, so that the work may bepositioned without interference by the drill, while the intermittentwithdrawals merely bring the tool out of the work's. suiilcien'tdistance to clear. the work of chips, etc., while the final movementremoves the toolfrom the work for the post .tioning'of a new piece. a

Further features of the construction are an parent in the renewingspecific tion and in conii inction with the Illl, and |2.-l2 of Fig.'"l.

- nections.

The accompanying drawings show by way. of

illustration the application of an intermittent or progressivefeedingmechanism according to this invention to a vertical drill, in which thefeeding mechanism is employed for feeding the drill 5 downward to thework, and then raising it from. the work. This particular embodiment isshown on'the several figures of the drawings, in which:

Figure 1 is a front elevation of a drill having s the inventionassociated therewith. 10

Figure 1a. is a fragmentary. section on line lw-la of Fig. 1.

Figure 2 is a diagrammatic chart showing the operation of the feedingmechanism.

Figure 3 is a horizontal sectional view, on a 15 larger scale, throughthe power supp u t, substantially on lines 3-3 of Figs. 1 and 5.

Figure 4 is a similar horizontal sectional view,- substantially on lines4-4 of Figs. 1 and 5.

Figure 5 is avertical sectional view along theaxis of the connectingshaft, substantially on line 5-5of Fig. 4.

Figure 6 is a horizontal sectional viewof the feed control mechanismsubstantially on line 66 of Fig. '7. 5

Figure '7 is a corresponding vertical sectional view, substantially onlines '|--'I of Figs. 1 and 6.

Figure 8 is a horizontal axial sectional view, on a larger scale thanthat of Fig. 6, of the nest' of gears and disks for controllin the f 30Figures is a detail sectional view, on the scale of Fig. 8,substantially on line 8-9 of Fig. '7.

Figures 10, 11 and 12-are successive vertical sectional viewssubstantially on lines iii-i0,

, Figure 13 is a fragmentary horizontal sectional.

view substantiallyon line ll-IS of Fig. 12, on a larger scale. v

Figures 14 to 19 inclusive are diagrammatic views showing the positionof the parts in the 40 feed control nest during a cycle of operation.

' Figure 20 is a circuit diagram of electrical con- The mechanismcomprises a feed power structure which operates selectively forproducing the 45 rotation of a connecting shaft in one or the otherdirection, so that a slow rapid approach movement'of, the tool towardjhework. aslow feeding movement during which the. tool may operate upon thework. and then the-rapid reverse movement for withdrawing'the .tool fromthe work may be successively accomplished. The connectlug-shaft operatesa feeding structure whichin turn is directly connected with a feedcontrol 5 ments of the feed control system and of the tool holder are inunison. The feed control system selects the operation of the powerstructure, and

is further provided with means for intermittently causing the forwardfeedings and then the reverse feeding of the tool holder, and alsoincorthe drawings, includes'the provision of a column I0 upon which ismounted .a spindle'and feedcontrol structure support II. This structurecan be secured at any desired height on the column H). A drill table I2is likewise supported on the.col-' umn in any usual way, preferably withthe inclusion of means l3 for adjusting its position and height. Thecolumn ill is mounted on the base M. The support I I has a member i5 forguiding the quill iii of the drill, the spindle I being rotatable inthis quill and having a socket l3 at its lower end for the drill I9. Itwill be understood that the spindle ll may be rotated by any desireddevice (not shown). This quill and spindle therefore constitute a toolholder, the quill being provided with rack teeth for engagement by thefeeding pinion 20 which is mounted on a shaft 2| extending into thegeneral feed unit housing FH. A power unit housing PH is attached to thegeneral support l4 and is-cor'mected with the feed unit by a connectingshaft 22 preferably with telescoping parts for permitting the relativeup-' ward and downward movement of the feed unit housing FH along thecolumn l0, and withuniversal joints 23. i

The power structure is shown in detail in Figs.

3 3, 4 and 5. The general housing PH is provided with a top closingplate PHI, abottom closing plate PH2, and a rear plate PH3. Supported bythis rear plate PH3'(Fig. 3) is-a feed motor M having a shaft 30extending toward the main housing PH and having a small gear 3| keyedthereto and in mesh with a larger gear 32 on the power structure drivingshaft 33 which is preferably supported by anti-friction bearings 34 inthe duced end in proper axial relationship to the sec- 0nd verticalshaft 42. 1

The first vertical shaft 33 is provided below the webPH3 with a coggedlocking disk 43 (Figs. 4 and 5) which may be engaged by the finger 43 ofa locking arm 41 connected to a rock shaft 43 which is also connected toa control arm- 43 .hav-

ing a plunger armature 30 pivoted at its free end.

This plunger armature (Fig. 4) may be attracted by the solenoid coil 3|of the control system, when energized in the manner describedhereinafter, and-thus serves to rock the arms 49 and 41 andengage finger43 in the cogged latter stationary.

disk 43 to hold the 2,053,399 system and the tool holder, so thatthe'movewhen the solenoid 5| is de-energized, a return spring 46a,operates through the plunger 4'la'to disengage finger 43 from the coggedwheel 43. The stress in spring 46a may be regulated from the exterior byan-adjusting screw 43b.

Above the web PH5, the first vertical shaft- 33 is provided with gearteeth 52 within the cage 31.

The second vertical shaft 42 is similarly provided with gearteeth 53within this cage. Both sets of teeth 52 and 53 are in mesh with theteeth on a pinion 54 mounted for free rotation about a.

spindle 55 carried by the cage.

A friction plate 56 loosely surrounds a portion.

of the second vertical shaft 42, within the cage 31,

, but bears frictionally against a shoulder surface 51 on this .shaft.The friction member 53 is held in such frictional contact by the plungerpins 53 which are received in recesses of the upper surface of thefriction member 53, and are guided in apertures through the worm wheel36 (Fig. 5), and are urged downwardly by springs 53 which are adjustedby the screws.

The'upper end of the second vertical shaft 42 is illustratedas pirmed tothe sleeve 23a of the shaft 22.

The feed structure includes means for operatively associating theconnecting shaft 22 and the feed pinion shaft 2| and its feed pinion 20,and for driving in unison therewith the feed control devices. This feedunit includes a general housingFH having an inner face plate FPI (to thelower universal joint 23 (Fig. 1) of'the connecting left in Fig. 1 andthus adjacent the quill IS), an

FP3, and an wheel 13 constituting a-partof a sleeve structure whichissupported by an anti-friction bearing 14 in the inner face plate FPI,and by a plain bearing bushing 15 in the central web constituting apartfof the general housing FH (Fig. 6). A key 13 connects the sleeve toa bushing ll having a keyway 13 by which'it may be keyed to the feedpinion spindle 2| shown in dotted lines in Fig. 6.

' This sleeve also has gear teeth 13 thereon (Figs. 6 and 9) which arein mesh with the teeth of a gear 30 keyed to a countershaft 3| which isJournaled in the central web of the general housing F1! in the faceplateFP2,.- A second gear 32 on shaft BI is in mesh with the peripheral teethof the gear 33 preferably formed'of insulating material and mounted forfree rotation about a bearing sleeve 34 on the periphery of the sleeveThe shaft" also has a small'skewgear 33 keyed thereto and in mesh withaskew' gear 33 keyed to the cross shaft 31 (Figs..7 and 9) which isiournaled in the general housing and is held against axial movement by ascrew 33 engaged in a peripheral groove thereof (Fig. 'l) and has'keyedthereto, at its left-hand end in Figz 'l, a gear 33 which meshes with agear 33 in the feed control nest, and keyed to the spindle 3| (Fig. 8)of this nest. I

. .fl'he gears.33 and 33 are thus rptated in unison, bothforwardly andbackwardly, and preferably are rotated through equal angles for a givenmovement of the drill l3: this being accomplished by the ratios of thegearteeth and gears 13, 30, 32, 33, 33, 33, 33 and. A

' housing'FH. The armis normally drawn upwardly by a spring I92, Thefree or left-hand and upper end of this arm (Fig. '7) includes clamppieces I93 which receve an abutment screw I 94.

A contact brush I95 bears constantly on contact ring 99 and permits thesupply of current to this ring and thus to the cam member 95, regardlessof the angular position of the gear 93 and associated parts. This brushI 95 is insulatedly mount ed in the general feed unit housing FH.

The feed control nest includes the central spindle 9I which is keyed tothe gear 99 and which has a small external dial I I9 also keyed theretoso that the position of the dial reproduces externallythe position ofthe gear 99. This gear 99 is of insulating material and has a feedcontrol contact sector III (Figs. 8 and 11-) mounted thereon.

As shown in Fig. 11, this'contact sector has a major portion extendingperipherally through an ,angle of substantially 315 degrees At one endof this major portion is an inward extension I I la having a peripheralangle of substantially 30 degrees. A hollow driving pin H2 is mounted inthe gear 99 in electrical association with the contact sector III .(Fig.8) and is provided with an axial cavity to receive a contact brush I I3which is urged toward the right in Fig.3 by a spring.

- The gear 99. is also provided with a releasing cam piece H4 at itsperiphery. A pin II5 of gear 99- is engaged with one end of a spiralspring II9 having its other end connected to a pin II'I mounted in'afeed control disk I I9 which likewise is of insulating material withrespect to its inner portion, but preferably is provided with a wearresisting outer ring II9 of metal which is held for movement with theinner portion III by pins I29. This wear resisting ring II9 (Fig. 12) isprovided with a plurality of threaded axially directed apertures I2Ilocated adjacent its periphcry for selectively receiving a stop screwI22. A fixed stop member I29 is secured to the end plate FP3-by screwsI24 and-cooperates with the stop screw. I22 to limit the rotationalmovementof disk; supports an annular contact ring I29 which feed controldisk II9-.-I I9.

The insulated portion II9 of the-feed'c'ontrol is engaged at all timesby a contact brush I29 (Figs. 12 and 13) insulatedly mounted on the feedunit housing FE. The feed control disk II9 also supports an electriccontact and mechanical driving member I29 which is electricallyconnected to the conductive ring I29 (Fig. 9), and preferably has theshape shown in Figs. 13 and 14, as having a high portion extending awayfrom the plane ofdisk 9 toward gear'9i9,"and a low portion forming aramp I294: extending from this surface. The contact member I29 ismounted at the same radius. from the axisofshaft 9I as the ramp surfaceI294 before the hollow drivin pin .I I2 encounters the high portionofelectric con;

tact member I29.

Contact disk m is mounted. m... rotation about a sleeve I29 surroundingshaft 9|.

Gear I33 is provided with two peripheral rowsof holes comprising anouter row I34 and an inner row I35. The outer row of holes I34 is inalignment with the major portion III of the contact sector on gear 99,while the inner row of holes I35 is in alignment with the inwardextension IIIa thereof. Three brushes I39, I31 and I39 are located inthe outer row of holes at angular distances determined by the operationto be accomplished. A single brush I39 is likewise positioned in aproperly selected inner hole. vAs shown in Fig. 8, each of these brushesmay comprises. stem portion guided in the gear I33, a collar, a pressurespring for forcing the brush toward gear 99. and an insulating heelpiece I49 which bears against the smooth internal surface of the end capFP4, so that the gear I33 may be rotated without changing the relativeposition of the brushes I39-I39 with respect to one another.

' This rotation of the gear I33 may be accomplished a pinion I43 thereonin mesh with a gear I33.

The end cap FP4 is preferably held in position by screws I44. The gearI33 extends between opposedsurfaces of the end plate FP3 and end cap FP4(Fig. 8) so that upon tightening the screws |44-,t1ie geal' I33 is heldin position by a frictional resistance dependent upon the adjustment ofscrews I44.

' The metal-wear ring II9 of the feed control disk H9 is engaged by aneccentric locking cam I59. (Figs. '1 and 12), mounted on a shaft I5Iwhich has a crank arm I52 pivoted to a link, I53

and thus connected to the plunger I54 actuated by a resetting solenoidI55 carried by a housing I59 connected to the bottom of the housingstructure. A torsion spring I51 operates to hold the cam surface I59engaged with the wear ring II9,

for cooperation therewith as a retaining pawl.

Also mounted on the feed control nest shaft 9| is an arm I99. having apad piece I9I for engaging the adjustable screw I94 of the feed con-'trol lever I99 (Figs. 'l and 12) i This arm I99 also carries a rockableshaft I92 having an arm I93 for engagement with the release cam I I4,and also' a cam I94 (Figs. '7, 12;14-18) operating as an advancing pawlupon the wear ring 9.

The electrical connections may be as illustrated in Fig. 20. The feedmotor M is illustrated as of three-phase type for supply by thethree-phase conductors 2990,- 299b, 2990, which are connected tocontacts under the control of the bridges of a reverse relay RR and aforward relay FR, so that as these relays are selectively closed,current is delivered through the motor supply conductors 2910, 29"). 29lo. the connection. of conductors 29Ia and 29" being reversed in thetwo' relays, whereby to secure opposite rotation of the feeding motor Maccordingly as one or. the other relay is closed,- in the usual way.

- A main feedcontroi conductor 292 is connected to phase conductor 299aand thence through a .main control switch SW tothe control conductor.299. which Is connected to brush I91 enga ed with the major portion ofsector I and. to resetting solenoid coil I99, and thence'by conductor294 to a contact controlled by the forward ieedrelay'l 'i and thence.when this relay is tie-energised, by a 999 back too motor conductor20I-c. A branch conductor 200 from conductor 200 leads to ahand-starting switch HS and thence nected by a conductor 2"! with acontact of the bridgegin forward relay FR which is closed when the relayis de-energized, and thence by conductor 2I I to the coil 2| 2 of thereverse relay RR, and thence-by conductor 209 back to the phaseconductor 200c. Brush I26 is connected by conductor 2I3 with the coil 2of the pilot relay .PR and thence by conductor 2 I 5 with the motor conductor m. The pilot relay PR controls the bridge which closes a circuitwhen the pilot PR is de-energized,- extending from conductor-2W and byconductor 2I6, solenoid 5| which actuates the feed control linger 06(Fig. 4) and thence by conductors 2 I I and 209 back to phase conductor200c.

The control circuit for the reverse relay extends from conductor 203 byconductor 2 I0, the contact roller '90, the conductive cam 95, andthence to brush I05 and by conductor 2I9, contacts of the feeding relayFF which are closed when the relay is energized, and thence by conductor220, contacts in reverse relay RR which are closed when the relay isde-energized, conductor 22I, coil 222 of the forward relay FR, with areturn by conductors 2Il and 200 to phase conductor 2000.

, Brush I09 is connected by conductor 229 wi conductor 220.

Brush I36 is connected by a conductorf220 with contacts of forwardfeeding relay FF which are closed when the relay is energiud, and thenceby conductor-220a to conductor -20'I.

The operation of the structure is as follows:

As stated hereinbefore, this structure operates by departing from thenormal withdrawn position, and advancing the tool rapidly intoapproximation with the work, then advancing the tool slowly to the workand then operating upon the work, intermittently withdrawing the toolfrom the work for clearing chips, etc., returning the tool rapidlytoward the work, and again slowly feeding the tool for a further workingoperation which begins at a more advanced point. The intermittentwithdrawal and return is continued, each successive slow feedingstage-being shorter than the last preceding slow feeding stage; Finally,at a limit of feeding movement, the tool is again withdrawn and theparts are restored to the initial position ready for a further suchcycle of movements.

At the beginning of such a cycle of movements,

in the form of construction illustrated on the drawings, the drill andspindle are raised. The

pin. I22 is against stop I 20 (Fig. 14), so that disk H0 is in aninitial position. Cam piece H0 is engaged with arm I00 and the cam pawlI00 is free of the wear ring IIO. Gear 00 is thus in its initialposition. Cam .flvhas its highest portion against the roller 90, so thatthe lever I00 and screw I00 are in their lowest position for closure ofcontact between roller 00 and cam 90.

Switch HS is open and switch 8w may likewise be open. All relays are inde-energized (lower) positions in Fig. 20. All solenoids arede-energized, if switch Sin is open. Finger 00 is disengaged from thecogged wheel 0 In described the operation, it may preliminarily bebrought out that contacts 06-00 control the intermittentwithdrawal ofthe 'tool' from the work, the control by timing or distance beingeffected by the shape of cam 00 and'the time of engagement of pad IOIwith screw I00. Brush m in conjunction with sector In establishes thelimit of the forward feeding, and thusdetermines the bottom of the holedrilled, for example. Brush I controls the limit of the reverse feedingin the withdrawal 'of the toolintermittently from .the work. Relay FFcontrols the operation of the device during a cycle of movement, whileintermittent withdrawals are being accomplished. Brush I I3 controls thepoint of shifting from rapid forwardto slow forward feeding movement.

Brush I39 determines the position of the quill in the fully withdrawnposition when the cycle is completed.

With the parts in the initial position described, the cycle of movementmaybe started when the article of work is beneath the drill,-forexample, by closing the hand switch 810. The hand starting switch HS isthen closed momentarily. A clrcuit is now established so that currentflows from conductor 200a by conductor- 202, switch Sw, conductor 203,conductor 206, conductor 201, coil 200, conductor 209, back to phaseconductor 2000. Relay FF is thus energized and closes a circuit fromconductor 203 by conductor'2l0, roller 90, cam 95, through theintermediate means to brush I05, by conductor 2I9, contacts atrelay FF,conductor 220, contacts closed in relay RR when deenergized, conductor22I, coil 222 of forward relay FR, conductors 2H and 209, back to phaseconductor 2000. A holding circuit is also established upon closure ofrelay FF from,conductor.

200, through brush I01, sector III, brush I06, conductor 220, contactsof relay FF, conductor 220a, and thence through coil 200 and conductor200, back to phase conductor 200c. This relay FF remains energized solong as both brushes I01 and I36 are engaged with sector I I I. Theenergize- .tion of coil 222 closes forward relay FR and establishes aconnection of the three phase .conductors 200a, 200b, 2000 with themotor conductors 20Ia, 20Ib, 20Ic, so that the motor M is set in motionfor forward feeding.

As the motor M turns, it drives shaft 00, gear 0|, gear 02,. shaft 90,worm 05, worm gear 36, pivot pin 55, and (through the pins 50 andfriction member 68) the upper shaft 02. The lower shaft 39 is free toturn as the finger 00 is not engaged with cogged wheel 00. The shaft 02drives connecting shaft 22, and the driving shaft I0 of the tool unit,and thus the worm I2, worm \wheel I0, sleeve 10a, bushing 11, pinionshaft 2|, pinion 20, and the quill I0 is fed downward in Fig. 1. Thisgives a rapid forward feed. Also, the rotation of sleeve 10a turns gears00, 02, 06 and thus gear 00 and cam 00, as well as shaft 01, gear 09 andgear 00, so that cam 95 and sector III, In turn in unison with the quillmovement. The sector III is considered as turning in a clockwisedirection for the forward feeding (Figs. 14-19). "This rapid forwardfeeding movement continues, while the parts are turning, for example,from the tion of Fig. 14 to that of 'Fig. 15. 'The brush H0 in hollowpin II2 ultimately encounters the ramp surface I200 of pin I20. At thismoment a further circuit is closed from conductor 200, through brushI01, sector-I I I, pin II2, brush III (Fig. 8) for delivering current topin I20 and thus to contact ring brush I20 to conductor 2I0 (some oftheseparts being omitted in Fig. 20 for simplicity), and thence throughcoil 2I0'and'by conductor ill and motor conductor 20Ia to phaseconductor 200D.

I00 and through aosaaee I now established from conductor 208, throughworm 35 continue to turn the worm wheel 36 in between pins b to c.. Inturning, the cam piece Ild which is.

the same direction as before, but the friction member 56 now slips withrespect to the shoulder 51. Pin is carried in rotation with worm wheel36 and its pinion 54 operates as a planet pinion of an epicyclic gearinghaving a fixed sun gear 52 and a moving sun gear ,53 with differentnumbers of teeth. Hence the upper shaft "is turned at a lesser speedthan before, but in the same direction, and the quill It continues itsdownward movement but ata lesser rate, while the feed control devicescontinue to operate in unison therewith. The rapid feeding movement thusac- P complished is that shown on Fig. 2 by the dotted linebetweempoints a and b. It will be notedthat this rapid feeding movementterminates and the slow feeding movement begins before the toolencounters the top of the work. Thus there is no impact of the tool uponthe work at a high rate of speed.

This slow forward feeding continues, from the point b to the point d.During this movement,

the cam 95 has been turning in a counterclockwise direction so that aslight upward movement has been permitted lever I00 and its screw I06.Duringthe initial part of the movement of gear 90, after slow feedingbegins, the brush H3 rides upon the ramp surface I20a until finally thehollow pin H2 encounters thefupstanding portion I28 of this pin andestablishes a mechanical driv-. ing relationship between the gear 90 andthe feed control disk IIB, so that thetwo now turn at the same rate ofspeed. It will be understood that the distance of travel of the brush H3along the ramp I28a beforeme'chanical engagement occurs H2 and I28represents the distance of slow feeding movement of the drill before itencounters the work, i. e. the travel from point,

. rigid with gear 90 ultimately leaves the arm I03}.

, (Fig. 16) the arm I83 has at thesame time as the closing of thecircuit (at brush I I3) which controls the slow forward feeding (Fig.15). Thus, when the'mechanical driving connection between pins H2 andi281 begins lowered the cam pawl I64 onto the friction disk H8 and itswear rin I I9. Hence,-when the turning movement of disk H8 begins. thearm I60 is carried therewith. This arm is in tight frictionalrelationship to the gear and its spindle 9| The disk H0 and its wearring turn freely pastv the retaining cam pawl I50 (Fig. 12). Thus, thearm I00 and its pad I01 I are moving downwardly while the lever I00 andits screw I04 are moving upwardly. Ultimately the pad IIiI encountersscrew I04 and moves lever I00 to break the electrical contact betweenroller 00 and cam (at point d, Fig. 2). is thus broken from conductor203, through conductor 2I0, worm 98, cam 95, brush I05, conductor 2I9,contacts of r lay FF, conductor 220, contacts of reverse relay RR,conductor 22I, coil 222- and conductors 2" and 200.'

of forward relay FR, The forward relay FR is de-energized and moves toopen position to cut oil current from the motor M which then tends tocome to a standstill. This general opening movement of forward relay FR,however, closes contacts so that a new circuit is brush 3 again Thecircuit .ing maybe relay energizing circuit between conductors 220 andHI to prevent energizatlon of the two relays at the same time. t Theopening of forwar the circuit from phase conductor 2001) to motor"conductor Mia, and thus de-energized coil 2M of relay PR and also thelatch solenoid 5!. The

relay FR has opened l5 relay PR drops open and maintains thede-energization of solenoidliI. I RR closes, motor conductor 20Ib isconnected to when thereverse relay phase conductor 200a. Hence, the twoends .of I

the branch circuit throughconductors Zia-2w are both connected to phaseconductor 200a and. I I no current flows through coil M4 to re energizerelay PR. Hence, solenoid 5i remains de-ene rglzed. Springdta operatesupon de-energization of solenoid hi to remove finger 46 from the coggedwheel t3 and hence the reverse movement of motor M produces a rapidreverse feeding or withdrawal.

As the motor turns in the reverse direction, thedrive to the quill I6and the gears 00 and 83 is the same as before, but these parts are movedin the opposite direction. The retaining pawl I50 prevents a retrogrademovement of the wear rin 0 and the feed control disk II8 hrough theaction of its spring IIS. This ring therefore remains stationary andindicates the depth to which a drilling operation has been accomplished,

Le. a drilling to the depth d in Fig.2.

Also, the backward movement of cam 0% moves I lever I00 downwardly atthe same time'as the return movement of the gear 90 and spindle 95 movesthe arm I60 upwardly. Thus, the circuit is re-established from conductor203 by conductor 2I8, roller 98, cam 95, brush I05, conductor 24s,conductor 220, back relay RR. which are now open. Ultimately, sector IIIleaves brush I30 and thus opens the circuit through energizing coil 2I2.The reverse relay RR. now opens again and the motor M is deenergized. 1In opening relay RR, however', the circuit through the forward relay0011- 222 is closed again, the motor M is brought to a-standstill of itsreverse movement, and the rapid-forward movement starts. During thisrapid withdrawal movement. the drill has moved from the point at topoint e on Fig. 2.

During the succeeding rapid feeding movement, the drill is advanced. topoint 1 at which encounters the ramp I281: and through the same circuitsas beforere-energizes solenoid 0| and thus causes the slow feedingmovement. 1

. During this withdrawal movement, however, the return of arm I60 hasnot initially occurred. owing to the engagement between cam pawl I60 tothe contacts of reverse and wear ring I10. when gear 00, however. turnsuntil. the cam piece I again engages the arm 8......t.l.fls.-.engagement is released and the arm I00 is now turned backto its stop I00a: a spring 101a (Fig. '7) connected to the. end of thepivot for arm I I03 and cam I0l ,,and to the main housemployed toassist. if i desired. As

shown in Fig. 17, however. the feed control disk H8 and its'stop pinsI22 and I28 are not returned during this movement. Thus the travel ofbrush I I3 until it encounters the arm I28 is successively greater foreach intermittent forward feeding, so that the drill is brought to slowfeeding movement, on each occasion, at a greater depth in the work, buton each occasion at substantially the same distance between the point ofthe drill and the work, as determined by the angular length of the rampI 28a.

. Likewise, at each successive intermittent feeding, the screw I04 israised a greater distance by its spring I02 as the cam 85 recedes aboveit, so

that theengagement of pad I6I is occurring at a less distance orincrement of slow feeding movea has been established by the position ofbrush I36 in gear I33, and by the angular position of this gear, thesector III leaves brush I36 and thus opens the holding circuit which hasbeen existing from conductor 203 through coil 208. Relay FF isde-energized, and thus the holding circuit is broken at the relay FF, aswell as the intermittent motion control circuit through conductors 2I9,220. The de-energization of relay FF,-

however, now closesa circuit from conductor 203,- through coil I55,conductor 204, contacts of relay FF, conductor 205, and motor conductor20Ic to energize coil I55, which pulls holding cam pawl I50 away fromthe wear ring I I9, so that this ring and its disk II8 may turnbackwardly under the action of spring II6 until stop pin I22 againencounters the fixed stop I23. Also, the de-energization of relay FF, byopening the circuit through conductors 2I8220 has de-energized coil 222of forwardrelay FR, sothat this relay Y, opens, and the motor M isde-energized. However, sector extension II In leaves brush I39 and 7ever, the relay FR then closes the reversing control circuit fromconductor 203 through brush I31, sector III, brush I38, conductor'2l0,contacts relay FR, conductor 2| I, coil 2I2, and conductor 203. Reverserelay RR closes to energize the motor M in the opposite direction andalso to maintain the energization of solenoid I55. At the limit of thebackward movement, brush I38 is-released by sector III, and the circuitthrough reverse relay coil 2I2 is open, so that the reverse relay RRmoves to open position and de-energizes motor M. Since, however, thecontrol circuit for energizing coil 222 of the forward relay FR is nowopen at relay FF, 9. further backward energization does not occur, andthe motor continues to coast and turn sector III. During this move--,ment, sector extension Illa may encounter brush I38 .and thusclose afurther circuit fromconductor 203, through brush I31, sector III,extension IIIa, brush I39, conductor 223, conductor 220, contacts ofrelay RR, conductor 22I, coil 222, and conductors 2I1 and 209, back tophase conductor 2000. The forward relay FR is energized,

I the motor is brought to a standstill and given a short forwardmovement. Immediately, howopens this control circuit, so that theforward relay FR drops to open position before the motor M has regainedspeed.

All parts have now been restored to the initial position, and the deviceis ready for a new actuation upon closure of a circuit betweenconductors 206 and 201. V

If for any reason'the sector III is not brought to a standstill, owingto failure in the control system, it may turn in a counterclockwisedirection from the position of Fig. 14, until it leaves the brush I31,which immediately opens the holding circuit for relay FF and of otherfeed control connections, and thus both relays ER and RR are open andthe system comes to a standstill. That thtis has occurred will beimmediately revealed by the position of dial I I in conjunction with theindex (Fig. 1).

Further, the operation of drilling is indicated by dial IIO, as thisdial turns through an angle corresponding to the linear movement ofquill I6. The brushes I36, I31, I38 and I39 are positioned in the gearI33 (Figs. 8 and 10) and control the limit of forward feeding movement(brush I36), the limit of return during intermittent withdrawal (brushI38), and the final withdrawal position upon the closing of the cycle(brush I 39) while brush I31 is a general feed brush to sector I I I.Hence, it is possible to adjust the feed withbut changing the length ofthe various strokes during a complete feeding cycle by merely rotatingthe gear I33, which may be accomplished by the external knob MI in themanner described above. This is particularly valuable, as it is possibleto remove the drill I9, grind it, replace it, and then reset the entirestructure for accurate operation without any change of the position ofdogs, brushes, or like elements.

In order to provide a self-containedstructure, it is preferred, -asshown in Fig. 7, to provide a terminal plate 300 at which the variousconductors from the control nest, from brush I26, from roller 98, andfrom brush I may be connected.

It will be understood that while this mechanism and apparatus has beenshown in conjunction with a drilling tool, it is applicable toemployment with other devices in which such a type of feedingis'valuable, and that it maybe employed in many ways within the scope ofthe -appended claims.

Having thus described the invention, what I claim as new and desire tosecure by Letters Patent, is:

1. In a drilling apparatus of the class described, a frame, a drillspindle movable relative to the frame, means for reciprocating thespindle, a contact cam moved with the spindle, a lever hav- "ing acontact cooperative with the surface of said earn, a control memberadvanced in unison with said spindle, an element actuated by saidcontrol member for moving said lever to separate said contact and saidcam, means for normally preventing return movement of the controlmember, and circuit devices including said contact and cam and meansforcontrolling said reciprocating means for effecting reciprocatingmovements thereof, said cam and control members cooperating to varytherequired movement of said element before said lever is caused to effectsaid separation.

2. In a drilling apparatus of the class described, a frame, a drillspindle movable relative to the frame, means for reciprocating thespindle, a first control member moved in unison with said spindle, asecond control member, first interengaging means on said first controlmember and second member in one direction, means for normally preventingretro grade movement of said secondcontrol member, an arm, secondinterengaging means on said arm and second controlmember whereby thesecond control member during its own movement moves said arm, meansmovedwith said first control for releasing-said second interengaging meanstact cam also moved in unison with said member..

a lever having a contact cooperating with said cam, said arm engagingsaid lever to separate said contact from said cam after a movement ofsaid arm determined by the shape and position of the cam. a

' 5. In a drilling apparatus of the class described, a frame, adrillspindle movable relative to the frame, means for reciprocating thespindle, a

contact sector rotated in unison with the :movement of said spindle, acontrol member, first interengaging means on said sector and controlmember whereby the sectormoves said control menr- "her in one direction,means for normally preventing retrograde movementof said control member,

an arm, second interengaging means on said arm and control memberwhereby the control member during its own movement moves said arm, meansmoved with said sector for releasing said second interengagingmeans.during the .movement of said sector. in the other direction, meansfor-returning said arm, a contact moved by said arm upon movement insaid one direction, a cooperating contact, further contacts cooperativewith said sector, and circuit means including said contacts forcontrolling said reciprocating means.

6. An apparatus as in claim 5, in which said sector has a portion whichat the end of apredetermined movement of said spindle escapes from oneof said further contacts, and said circuit means extending through said.onefurther contact includes devices for releasing said normal preventingmeans, together with means for-returning said control member to initialposition.

'7. An apparatus as in claim 5, including a movable member providing aninsulating support for at least a portion of said further contacts,whereby movement of said movablesplndle -,will determine the positionsof said member relative to said frame at which said moving meansiscontrolled without change of the distances of movements of saidspindle thus controlled.

.a' frame,

gear and a gear train .unison with the spindle, a contact sector on saidgear, pin means'carried by said gear inelectrical 8. In a drillingapparatus of the class described,

a drill spindle movable relative to the frame, means for reciprocatingthe spindle. a for rotating said gear in connection with said sector, acontrol member colug on said controlflmems and including a portionengaged by said pin meansfor driving said control member, and a contactportion engaged by said pin means before the driving begins, contactmeans actuated by said control member after a movement there .means for'holding against return movement, means controlled by the gearforreturning the gear for returning said control member the contactmeans with the gear, and a contact for supplying current to said-sector,limit contacts disengaged by .said

sector upon predetermined movements of said spindle in the oppositedirection, and circuit.

' said contact'portion, thereafter a slow forward.

movement until said contact means is actuated, and then a rapid returnmovement until said sector leaves said limit contact, in succession,

,each forward movement being to a greater distance as. said controlmember carries said his forward. 9. In a'drilling apparatus ofv the"class described, a frame, a drill, spindle movable relative to theframe, means for reciprocating the spindie, a gear and a gear train forrotating said gear in unison with the spindle, a contact sector on saidgear, pin means carried by said gear in elecmember in the .path of'movement of said pin means and including a portion engaged by saidtrical connection withsaid sector, a control member coaxial with saidgear, a lug onsaid control pin means for driving said control member,and

a contact. portion engaged by said pin means before the drivingbegins,contact means actuated bysaid control member after a movementvthereof," means for holding said control member against return movement,means controlled by the contact means with the gear, and a contact-forsupplying current to said sector, a limit contact disengaged by saidsector upon a predetermined movement of said spindle in the otherincluding said contact, sector, pin, contact portion and contact meansfor controlling said reciprocating -'means,- whereby a rapid forwardmovement occurs until said pin engages said contact portion, thereaftera slow forward movement until said contact means is actuated, and thena, rapid return movement until saidsector leaves said limit contact, insuccession,

trol member carries said lug forward.

10. A drill having a frame including .a holder for a piece of work, arotating spindle movable eluding a feed determining device moved inunison with the spindle, a feed limiting device adeach forward movementbeing to a greater distance as said condirection, and circuit meansvanced when the spindle is moved- Jorward,

means for moving said feed devices toward one another during the forwardmovement of the spindle, meansfonholding the limiting against returnmovement when the spindle is moved backward, andmeans includingcooperating devices actuated with the said devices for controlling saidfeeding means toproduce successively rapid forward movements, eachfollowed by a slow forward movement and a return movement. saidcooperating devices comprising interengaging abutments.

11. In a drilling apparatus of the class de,- scribedsa frame, adrlllspindlemovable relative to the frame, means for reciprocating the drillspindlefand means-for controlling said recipro+ f eating means wherebysaid drill spindleis alternately movedi'orward and thereafter returnedin cycles, each said forward movement being greater than thelast'succeeding forward movemerit by a successively decreasing amount;said controlling means including two abutment struc device tures andmeans for moving the same with said drill spindle and difierentiallywith respect to one another to effect engagement of the same, devicesoperatively controlled upon engagement of the structures to cause saidcontrollingmeans to terminate the forward movement and initiate a returnmovement, one said abutment structure comprising a single adjustableelement. engaged by the other said abutment structure to determine theamounts of all said forward movements, and devices includedin saidabutment structures and reciprocating means for causing said adjustableelement to engage the other said abutment struc-, ture at a differentposition of said spindle for each forward movement thereof and with eachforward movement greater than the last succeedto the frame, means forreciprocating the spindle, control. members moved in unison with saidspindle, and devices'selectively engaged by said control members forcontrolling saidreciprocatingmeans whereby said spindle isalternatelymoved forward and thereafter returned, each said forward movement being,greater than the last succeeding forward movement by a successivelydecreasing amount; said controlling means ineluding two abutmentstructures and means for moving the same with said spindle anddiflerentially with respect to one another to effect en gagement of thesame, devices operativelycontrolled upon engagement of the structures tocause said controlling means to terminate the forward movement'andinitiate a return movement, one said abutment structure comprising asingle adjustable element engaged by the other said abutment structureto determine the amounts of all said forward movements, and devicesincluded in said abutment structures and'reciprocating means for causingsaid adjustable element to engage the other said abutment structure at adifferent position of said spindle for each forward movement thereof andwith each forward movement greater than the last succeeding forwardmovement by a successively decreasing amount.. Y

;13. In a drilling apparatus ofthe class described, a frame, a drillspindle movable relative to the frame, means for reciprocating thespindle by successive rapid forward movements each followed by a slowforward movement and a return movement, a traveling element carriedcontinually forward by the spindle during each successive slow feedmovement for the purpose of governing the point of each succeeding shiftfrom rapid forward to slow forward movement, means for detaining hetraveling element in ,its successively moved positions during the returnmovement of the spindle, an abutment movable with said spindle andengaged by the traveling element to determine the amount of each forwardmovement, control means operatively controlled by the engagement of thetraveling element and abutment for causing saidproducing means to eflecta return movement, and means for releasing said detaining means and forautomatically returning said traveling element to the starting positionduring the final return movement of the spindle. r

14. An apparatus as in claim 13, in which the abutment comprises areciprocable. element which is fed forward predeterminable distances byand with each advance of the traveling element for aosasao the purposeof controlling said control means for shifting from the slowforward'feedmoveme'nt to the return movement, and'a contact elementincluded in said traveling element and operated upon contact of thereciprocable element with said traveling element.

15. In a drilling apparatus of the class described, a frame, a drillspindle movable relative to the frame, electrically controlled means forreciprocating the spindle by successive rapid forward movements eachfollowed by a slow feed movement and a return movement, a travelingelement containing a limit contact carried continually forward with thespindle during each successive slow feed movement for the purpose of.goveming the point of each succeeding shift from rapid forward to slowforward movement,

means for detaining the traveling element in its successively advancedpositions, an abutment moved with and toward said traveling elementduring the forward movement and operating uponengagement therewith toactuate said limit contact and moved back with said spindle during thereturn movement, and means controlled by said limit contact forautomatically returning said traveling element to the starting positionduring the final return movement of the spindle.

16. In a drilling apparatus of the class de scribed, a frame, a drillspindle movable relative I tov the frame, and means for reciprocatingthe spindle to feed the tool to the work; said means including areversible source of power, feed transmitting elements connecting thesource with the spindle and including a device for changing the speedratioof transmission, and feed control devices including parts actuatedwith said spindle, said partsincluding two abutments which uponengagement actuate said controlled reversing means, means for movingtheabutments toward one another during the forward feeding of thespindle and operating forsuccessively advancing one said abutment to agreater distance at each cycle of movement by an increment of distancewhich is less than the preceding increment, and

means controlled by said parts for reversing said source after a returnmovement of'the spindle and also effective for actuating said speedchanging device for producing cycles of movement each comprising a rapidforward movement followed by a slow forward movement and a returnmovement. v

17. An apparatus as in claim 16 in which the said controlled reversingmeans includes devices operating to terminate each said rapid forwardmovement short of the end of the prior slow forward movement.

18. An apparatus as in claim 16 in which said controlled reversing meansincludes devices operment short of the end of the prior slow forwardmovement, and means operated after a forward movement of predeterminedamount for causing said reciprocating means to' produce a final returnmovement and for detaining the spindle in withdrawn position.

19. An apparatus as in claim 16 in which the said controlled reversingmeans includes devices operating to terminate each said ranid forwardmovement short of the end of the prior slow forward movement, and meansoperated after a forward movement of] predetermined amount for causingsaid reciprocating means to produce a final return movement and fordetaining the spindle in withdrawn position, and in which the severalsaid means include two' withdrawal limit devices, one said deviceoperating during the intermittent feeding tocause the-initiation ofsuccessive cycles of forward and return movements,

of predetermined amount for the purpose of detaining the spindle at afully withdrawn position and following a. return movement greater thanthe return movements during the phases of intermittent operation.

EDWARD JOSLIN KINGSBURY.

